When a power of attorney has taken a large amount of money out of the vulnerable senior's bank account, and put it into the power of attorney's name, then that sounds like theft to me. (I know that the senior can hardly communicate verbally these days, so he did not tell her to do this, and the poa lives out of town, so isn't able to even visit much).
What is the next step to have the money returned to the senior, and to get this person's name taken off as poa?